On 8/13/20 8:34 AM, Niklas Schnelle wrote:
On 8/13/20 12:40 PM, Niklas Schnelle wrote:
On 8/13/20 11:59 AM, Oliver O'Halloran wrote:
On Thu, Aug 13, 2020 at 7:00 PM Niklas Schnelle <schnelle@xxxxxxxxxxxxx> wrote:
On 8/13/20 3:55 AM, Oliver O'Halloran wrote:
On Thu, Aug 13, 2020 at 5:21 AM Matthew Rosato <mjrosato@xxxxxxxxxxxxx> wrote:
*snip*
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index 3902c9f..04ac76d 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -581,6 +581,14 @@ int pcibios_enable_device(struct pci_dev *pdev, int mask)
{
struct zpci_dev *zdev = to_zpci(pdev);
+ /*
+ * If we have a VF on a non-multifunction bus, it must be a VF that is
+ * detached from its parent PF. We rely on firmware emulation to
+ * provide underlying PF details.
+ */
+ if (zdev->vfn && !zdev->zbus->multifunction)
+ pdev->detached_vf = 1;
The enable hook seems like it's a bit too late for this sort of
screwing around with the pci_dev. Anything in the setup path that
looks at ->detached_vf would see it cleared while anything that looks
after the device is enabled will see it set. Can this go into
pcibios_add_device() or a fixup instead?
This particular check could go into pcibios_add_device() yes.
We're also currently working on a slight rework of how
we establish the VF to parent PF linking including the sysfs
part of that. The latter sadly can only go after the sysfs
for the virtfn has been created and that only happens
after all fixups. We would like to do both together because
the latter sets pdev->is_virtfn which I think is closely related.
I was thinking of starting another discussion
about adding a hook that is executed just after the sysfs entries
for the PCI device are created but haven't yet.
if all you need is sysfs then pcibios_bus_add_device() or a bus
notifier should work
So this might go a bit off track but the problem is that
on s390 a VF can be disabled and reenabled with disable_slot()/enable_slot().
In this case pcibios_bus_add_device() is not called again but
the PF/VF link needs to be reestablished.
Scratch that I must have made some stupid mistake last time I tried
this, with your suggestion I tried again and it works perfectly
moving the setup into pcibios_bus_add_device().
Thank you, this is actually much nicer!
OK, and I can likewise relocate the setting of detached_vf to
pcibios_bus_add_device().
